The inflatable shaping system reducing the aerodynamic drag upon the rear of a vehicle generally relates to drag reduction devices and more specifically to an inflatable and deflatable device that alters the shape of the rear of a trailer or truck. The present invention reduces the aerodynamic drag caused by the blunt rear ends of over-the-road semi trucks and trailers. The present invention utilizes inflatable members that stretch a covering upon the rear of a trailer which alters the shape of the trailer encountered by air flow during motion. The altered shape of the trailer lessens drag and improves fuel mileage for is trailers and trucks.
Various goods, commodities, and equipment move around the country by truck. Trucking moves goods and cargo from a loading destination to an unloading destination over roads and highways nationwide. The unloading destination often includes a specific address to a door, a dock, or a building. Unlike other modes of freight, trucking allows for point to point movement and delivery. In recent decades, manufacturing has moved closer to a just in time inventory model where parts and goods arrive at a factory within hours of their assembly into a finished good. Trucking with its timely and precise delivery has brought about just in time inventory now prevalent in manufacturing.
Trucking utilizes tractors and trailers, and for smaller loads, trucks without trailers. Tractor and trailers also have the name of semi-trailer or semi. A tractor trailer travels with the tractor in the lead. Motion of the tractor trailer generates a flow of air about the tractor and its trailer. The tractor often has a short front about six feet tall over the engine and ahead of the windshield. At the windshield and rearward, the tractor has its maximum height of approximately ten feet. The air encounters the leading edge of the truck, the engine, and flow over the engine to the windshield. There, the air flow changes direction and flows upwardly to the top of the truck, generally the cab.
Behind the cab, the tractor trailer has its trailer. The trailer has a height of approximately twelve feet with a few feet exposed above the cab. The trailer has its front proximate the cab and its rear generally away from the cab. When the tractor trailer moves forward, the air flow once more changes direction from over the cab to upwardly at the front of the trailer and then flat over the trailer. At the end of the trailer, the air flow then drops downwardly and curves inwardly behind the rear of the trailer. When the air flow drops, it creates an eddy region behind the rear of the trailer. The eddy region disrupts the air flow after the tractor trailer is making the flow less than laminar. The disrupted air flow causes turbulence behind the rear of the trailer which slows the speed of the tractor trailer as a drag force. The driver of the tractor trailer compensates for this by additional throttle upon the engine. The additional throttle raises fuel consumption for the tractor. Though this background material refers to a tractor trailer, the flow of air over the engine and cab of a truck without trailer has much in common.